Schill93- 1/4" seams for piecing are standard when piecing traditional blocks or using a pattern and you will need to stick with that when following a pattern if you want your blocks to come out the correct size. However, if you don't mind drafting your own patterns, or if you are mainly interested in improv piecing then you don't need to worry about your seams being 1/4" or scant 1/4". In any case, since you've got the Juki 2010, you can use that to do any piecing that requires precision 1/4" seams.
The drawback to piecing with the left homing machines is that you end up having a situation when sewing a 1/4" seam where the right feed dog does not properly engage the fabric unless you turn your work so that the bulk of the fabric is contained in the harp- in other words, instead of reading your quarter inch from the right side of the foot, you are reading it from the left side. That can get to be a pain when you're putting a big quilt together because of having to put the bulk of the quilt through the harp, but it's no big deal when working on a smaller piece once you get used to it.
If you don't turn your fabric so that it is all inside the harp, then your right feed dog won't be covered when sewing your quarter inch seam and that causes the fabric to veer away- which is also a major pain.
If you enjoy sewing on the Kenmore, then by all means go for it. I love mine, though it does require a lot more maintenance than my PQ1500s (similar to your Juki2010). I use my PQ1500s whenever I'm working on a piece that requires 1/4" seams and generally only pull out the Kenmore when I'm working on home dec.
Farmhousesewer- I mentioned the fellow who jury rigs his left homing 1914 to straight stitch in a center needle position because I thought it was kind of interesting. He tends to do things with his sewing machines that are a bit out of the ordinary and I enjoy seeing folks tinker with their machines to see just what they can get them to do- for me, that's part of the fun of sewing
Rob